However, it's not enough to stop them from working hard to keep her memory alive in hopes of continuing their healing process.

On April 2, 2008 Zimmermann, 21 years old at the time, was found dead in her Doty Street apartment. She was discovered by her fiance after a Dane County 911 dispatcher dropped her cell phone call for help.

Despite numerous tips and efforts to solve her murder, police have not identified her killer.

Five years after the crime, a new crop of students and neighbors do not know Zimmermann's story.

"I hear about the Brittany Run every year, but my sister's a freshman here, and I don't think she has a clue what it's even about," said UW senior McKenzie Kirkland, who lives near Zimmermann's former apartment on Doty Street.

But for Zimmermann's mother, Jean, five years isn't enough time to erase the daily struggle of not knowing what happened to her daughter.

"Of course life without her is huge. Basically we really would like to know who did it and why," said Jean Zimmermann.

Madison police said there's nothing new to release and declined an interview, leaving many questions unanswered for Jean Zimmermann.

"It's not their fault. They've extinguished their avenues that they had been down. It's really hard for us to understand that this person is still walking around," she said.

Extinguished avenues haven't stopped Jean Zimmermann from being a voice for her daughter. She continues to push for legislation that would require suspects to surrender DNA when arrested, something she thinks would help solve not only her daughter's case but others as well.

"I will go to every meeting in order to make this happen," said Zimmermann.

UW Police Officer Erik Pearce, a board member for the annual Brittany Run, which takes place in Zimmermann's memory, said her friends and family are looking for closure.

"It's important to find Brittany's killer to help the family heal, help the community heal and give everybody peace of mind and closure," said Pearce.

The reward fund for information on Brittany Zimmermann's killer is now at $40,000. Anyone with information is asked to contact Crimestoppers at 608-266-6014.

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